* {
    padding: 0;
    margin: 0;
    text-decoration: none;
    box-sizing: border-box;
}

.header {
    width: 1700px;
    height: 100px;
    font-size: 50px;
    margin: 3px auto;
    color: #fff;
    position: relative;
    background-color: skyblue;
    padding: auto;
    line-height: 100px;
    text-align: center;
    font-weight: 700;
}

.a1 {
    position: absolute;
    right: 30px;
    font-size: 30px;
    color: red;
}

form {
    width: 900px;
    height: 600px;
    display: flex;
    border: 4px solid pink;
    flex-direction: column;
    border-radius: 20px;
    margin: 60px auto;
    justify-content: space-around;
    position: relative;
    padding: 25px;
}

button {
    width: 850px;
    height: 60px;
    font-size: 30px;
    /* line-height: 100px; */
}

label {
    font-size: 30px;
}

input {
    width: 600px;
    height: 55px;
    padding: 20px;
    font-size: 30px;
}

span {
    position: absolute;
    top: 15px;
    /* margin: 10px auto; */
    font-size: 30px;
    color: red;
    left: 350px;
    display: none;
}

.act {
    display: block;
}